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<?php echo preg_match('/Я/ui', 'я'); echo preg_match('/(?=Я)/ui', 'я'); echo preg_match('/Л/ui', 'л'); echo preg_match('/(?=Л)/ui', 'л');
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/Op0GK
function name:  (null)
number of ops:  9
compiled vars:  none
line      #* E I O op                               fetch          ext  return  operands
-----------------------------------------------------------------------------------------
    3     0  E >   FRAMELESS_ICALL_2                preg_match          ~0      '%2F%D0%AF%2Fui', '%D1%8F'
          1        ECHO                                                         ~0
    4     2        FRAMELESS_ICALL_2                preg_match          ~1      '%2F%28%3F%3D%D0%AF%29%2Fui', '%D1%8F'
          3        ECHO                                                         ~1
    5     4        FRAMELESS_ICALL_2                preg_match          ~2      '%2F%D0%9B%2Fui', '%D0%BB'
          5        ECHO                                                         ~2
    6     6        FRAMELESS_ICALL_2                preg_match          ~3      '%2F%28%3F%3D%D0%9B%29%2Fui', '%D0%BB'
          7        ECHO                                                         ~3
          8      > RETURN                                                       1

Generated using Vulcan Logic Dumper, using php 8.5.0


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